ruri 瑠璃

Lapis lazuli. Vaidurya in Sanskrit. Originally it meant lapis lazuli or emerald, but from the Six Dynasties period Chinese used the term for glass beads similar in appearance. From the Ming dynasty ruri indicated sansai 三彩 glaze or ruri glaze. In Buddhist scripture it appears frequently as the blue jewel. It is always the third in the four jewels (gold, silver, lapis lazuli, crystal) and in the seven jewels (gold, silver, lapis lazuli, crystal, Tridacna gigas, coral, and agate) of Buddhism.